Heathrow airport is expecting its busiest weekend of the year as millions of Britons head off for their summer holidays.

Most pupils across the UK began their six-week break on Friday, with Heathrow expecting 1.4 million passengers to jet off between Friday and Sunday. BAA said 13.7 million people will use the airport over the school holidays. Heathrow's last peak period, in the runup to Christmas, saw travel plans for hundreds of thousands of passengers disrupted by heavy snowfall that shut the airport for several days.

This time, the biggest challenge is getting thousands of families through terminals. Terry Morgan, acting chief operating officer at Heathrow, said: "We're looking forward to a very busy summer and hope family-friendly initiatives such as dedicated family lanes and children's play areas will take the load off parents and get holidays off to a flying start."

At Gatwick, Britain's second largest airport, 250,000 people are expected to fly out over the weekend, with a further six million using the airport over the school holidays. Drivers have been warned to expect traffic jams with around 14m cars on the roads as schools finish early. The AA said roads leading to south-west England were likely to be the busiest, with congestion on routes to the coast, airports and cross-Channel ports.

The Met Office said next week's weather should be warmer and drier, in contrast with the torrential conditions seen by much of the UK in recent weeks.